Aim:To explore the volatile topographic changes occurring in the palatal rugae after aging and loss of all teeth. Materials and methods: The total sample consists of 40 Iraqi participants in 2 , dentate and edentulous , groups. Their maxillary casts were minutely observed. Number, lengths, qualitative characteristics, and medial position of the rugae ends were recorded. Results: Many differences were observed between the 2 groups. Conclusions: Palatal rugae were topographically changed greatly after aging and loss of teeth regardless of time of edentulism and wearing dentures. Short , simple , scattered and anteriorly flared is the overall picture of rugae in edentulous palates .

Aims: Assessment of Candida albicans adherence to flexible denture base material (Valplast) and conventional heat polymerized acrylic resin in the presence and absence of saliva. Materials and Methods: A total of 28 square specimens (10 mm x10 mm x3mm) were constructed from Valplast and acrylic denture base materials according to manufacturers' instructions and kept without finishing or polishing. C. albicans was isolated from patients with denture stomatitis. Fourteen specimens (7 of each material) were not coated with human saliva (control), deposited in yeast suspension (10 7 ) yeast cells/ml, incubated for 1hr at room temperature and washed with phosphate buffer saline and then stained with crystal violet. The remaining 14 specimens (7 of each material) were coated with saliva and treated as previously described. Adherent yeast cells in 84 fields of view (0.25mm 2 /field) of materials were enumerated. The results were expressed as yeast cells/mm 2 of material. Results: In comparison between the two denture base materials, Candida adherence to acrylic resin (170 yeast cells/mm 2 ) is greater than Valplast (126 yeast cells/mm 2 ). Both saliva uncoated and coated acrylic samples have higher means of Candida adherence (208, 132 cells/mm 2 ) than saliva uncoated and coated Valplast samples (175, 77 cells/mm 2 ) respectively. High significant reduction in yeast counts was seen in both materials after saliva coating. Conclusions: Great reductions in yeast counts were determined in Valplast material specially in saliva coated specimens when compared with acrylic resin. Key Words: Candida albicans adherence, flexible denture base material, Valplast Ahmad ZM, Mustafa EA, Jawad IA. Adherence of Candida albicans to Flexible Denture Base Material. Al-Rafidain Dent J. 2012;12(2): 229-235.

Aims: The aim of this study was to evaluate the effectiveness of microwave irradiation sterilization on Molloplast-B soft denture liner. Materials and Methods: Sixty specimens of Molloplast-B soft denture liner were fabricated in a standardize procedure and autoclaved. The total 60 specimens were divided into 4 groups. Each group has 15 specimens inculated with Brain Heart Infusion Broth (BHI) media containing one of the tested microorganisms (Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeroginosa and Candida albicans). Then the 15 specimens in each group was further divided into 3 subgroups: group C (positive control); 5 none irradiated specimens, group D (dry microwave treatment); 5 specimens placed in a dry beaker and microwave irradiated at 540W for 6 minutes, group W (wet microwave treatment; 5 specimens immersed in distalled water and irradiated in the same manner as group D. After incubation of all specimens for 24 hours at 37°C, the specimens were got vortex and then the replicated specimens (100μL) of suspensions were plated on 4 selective media appropriate for each organism. All plates were incubated at 37°C for 48 hours. After incubation, colonies were counted. Further 7 days incubation for microwaved specimens was done to verify the effectiveness of dry and wet microwave sterilization. Results: Significant reduction in cfu/ml of all microorganisms was observed at 48 hours. No growth of C. albicans was recorded at 48 hours and after 7 days incubation. Conclusions: Microwave irradiation at 540W for 6 min in dry and wet conditions was proved to be effective in the disinfection of soft lining material specimens contaminated with Staph. aureus, Ps. aeruginosa and B. subtilis. Wet treatment was more effective than dry one. Dry and wet microwave treatment sterilized specimens contaminated with C. albicans.

Aims: To determine the level and angulation of the occlusal plane of the artificial dental arch by measuring the level and angulation of the occlusal plane of completely dentulous subjects and to find the relation of these measurements to some of the vertical facial and intra oral dimensions. Materials and Methods: The sample of the study consisted from 54 completely dentulous adult subjects (24 female and 30 male) with class 1 normal occlusion aged 19-24 years. Dental casts were taken for each subject, the level and angulation of the occlusal plane, vertical facial, and intra oral dimensions were measured using digital vernier caliper and protractor. The data were analyzed with statistical package for social science program. Results: Sexual differences were found in the intra and extraoral measurements. Most of the measurements dealing with the occlusal plane level and angulation were correlated with each other and with facial measurements. Conclusions: The level and angulation of the occlusal plane of the maxillary and mandibular dental arches as measured on the dental casts are higher in maxilla than in mandible and the intra and extraoral vertical facial measurements are greater in male than female.

This study assessed the effect of copolymerization on the microbiota of the oral cavity. The plant extraction was converted into aromatic derivatives, which were added to methyl methacrylate monomer. Fourier transform infrared spectroscopy spectra showed no negative effects of these additives on the polymerization process. All the assayed derivatives displayed some degree of antibacterial activity.

Aim: to determine the validity of the ala-tragus technique in orienting the occlusal plane in complete denture construction for edentulous patients by evaluation of the edentulous patient response. Materials and methods: Twenty edentulous patients were selected according to specific criteria. Sixty sets of complete dentures (three sets for each edentulous patient) with three different occlusal planes parallel to the imaginary line between the inferior border of the ala of the nose, and superior, middle and inferior borders of the tragus were constructed. The grade of participants' response in this research was studied to report the degree of their participation with the occlusal plane of the complete denture they used through answering of Denture Patient Satisfaction Questionnaire (DPSQ) after one month of using each of the three randomly selected complete dentures. Mean and percentage of all the scores (four scores totally satisfied and unsatisfied, fairly satisfied and unsatisfied) were calculated to give an idea about the participants' response. Results: showed greatest participants' satisfaction (75-90%) were obtained in the complete denture with middle and inferior occlusal planes. Patients satisfaction with denture 2 range between 80-90% regarding speech and chewing ability. Denture 3 (inferior occlusal plane) showed the greatest fairly satisfaction in 60% of patients originated from mandibular denture. Conclusion: most patients were satisfied with the dentures having occlusal plane be oriented parallel to the middle and inferior ala-tragus lines.